Cherenkov was promoted to section leader, and in 1940 was awarded the degree of Doctor of Physico-Mathematical Sciences. In 1953, he was confirmed as Professor of Experimental Physics. Starting in 1959, he headed the institute's photo-meson processes laboratory. He remained a professor for fourteen years. In 1970, he became an Academician of the USSR Academy of Sciences.

In 1934, while working under S. I. Vavilov, Cherenkov observed the emission of blue light from a bottle of water subjected to radioactive bombardment. This phenomenon, associated with charged atomic particles moving at velocities greater than the phase velocity of light, proved to be of great importance in subsequent experimental work in nuclear physics, and for the study of cosmic rays. Eponymously, it was dubbed the Cherenkov effect, as was the Cherenkov detector, which has become a standard piece of equipment in atomic research for observing the existence and velocity of high-speed particles. The device was installed in Sputnik 3.